Search PubMed⌕ Search

Biomedical subjects

T Kozuka

Publications and source records attributed to T Kozuka.

At least 199 records · Page 11Linked to original sources
PubMed1989

Portosystemic collaterals in portal hypertension: visualization by using blood-pool SPECT imaging.

Single-photon emission CT (SPECT) was performed with technetium-99m autologous RBCs in 11 patients with chronic hepatitis and in 46 cirrhotic patients with portal hypertension to determine the value of the procedure for identifying portosystemic collateral blood flow. Twenty millicuries (740 MBq) of 99mTc-RBCs, labeled by an in vivo technique, were given IV, and tomographic imaging of the intraabdominal vascular blood pool was performed. Fourteen patients with cirrhosis also had arterial portography, and 37 had scintiphotosplenoportography. In 38 of 46 patients with cirrhosis, SPECT images showed portosystemic collaterals. The coronary vein was seen in 52% of the patients, the short gastric vein in 11%, the gastrorenal or splenorenal shunt in 24%, the umbilical vein in 11%, and the anterior abdominal wall vein in 17%. Portosystemic collaterals were not shown in any of the patients with chronic hepatitis. Collaterals were identified on SPECT images in 10 of 11 patients in whom collaterals were documented by arterial portography and in all 28 patients in whom collaterals were shown by scintiphotosplenoportography. Furthermore, SPECT clearly showed a patent portal vein in three patients and the coronary vein in two patients, when these veins were not identified by means of scintiphotosplenoportography. This experience suggests that SPECT is useful for the noninvasive identification of portosystemic collaterals in patients with portal hypertension.

Adult↗
PubMed1989

[The role of radiation therapy in treatment with preservation of shape and function in intraoral cancer].

The goal in treating intraoral cancer is to obtain tumor control with preservation of shape and function of oral cavity. For T1, T2 lesions of the tongue, the floor of the mouth and the cheek mucosa, interstitial radiation therapy provides a control rate of 80-90% with excellent preservation of function. With surgical salvage for persistent or recurrent tumor, the ultimate control rate is 90-95%. Unfortunately, for more advanced lesions surgery is frequently required to obtain local control. The use of bleomycin or peplomycin in simultaneous combination with external radiation therapy provides a good chance of local control without surgery. For T1, T2 lesions of the lower gum and the cheek mucosa complete response rate is approximately 65% and 70% of these are cured without surgery. With surgical salvage for persistent or recurrent tumor the ultimate control rate is 90%. For most of the poor responders surgery or interstitial irradiation is required to control the tumor.

Bleomycin↗
PubMed1989

[A case of tracheopathia osteoplastica].

A case of tracheopathia osteoplatica in a 43-year-old man, detected incidentally at the upper gastrointestinal examination was reported. The examination showed a long segment esophageal compression from a paraesophageal lesion. CT was effective to demonstrate the typical narrowing and wall thickening of the trachea, and to demonstrate that the esophageal compression was caused by the deformed trachea.

Adult↗
PubMed1989

[Estimation of myocardial viability in left ventricular regions with akinetic wall motion by postextrasystolic potentiation using list-mode radionuclide ventriculography in an interesting case with silent ischemia and with premature ventricular complexes (quadrigeminy)].

For determining an indication of percutaneous transluminal angioplasty (PTCA), a 73-year-old-man with silent ischemia and with ventricular premature complexes (quadrigeminy) were performed cardiac nuclear studies. This case had 99% stenosis in LCX (#11) and 90% stenosis in RCA (#1), and demonstrated akinetic wall motion in left ventricular (LV) inferior and posterior regions. Exercise-redistribution Tl-201 studies indicated myocardial viability in a portion of the inferior wall but not in the posterior wall. To estimate the potential contractile function in the regions with akinesis, from the list-mode data of radionuclide ventriculography, those of postsinus beats and postextrasystolic beats were separately selected and were analyzed for investigating LV wall motion and LV ejection fraction (EF). With the post-extrasystolic potentiation, LVEF increased from 36% to 45% and the systolic wall motion was augmented in the inferior wall but not in the posterior wall. From these findings we recognized the existence of myocardial viability in a portion of the inferior wall. After PTCA for the RCA lesion, improvements of the myocardial Tl-201 distribution and LV wall motion in the inferior wall were definitely observed and hence LVEF increased by 16% to contribute to an increase in exercise performance. Thus, this case indicates that the postextrasystolic potentiation is useful for determining an indication of PTCA in patients with LV asynergy, demonstrating the myocardial viability and the potential LV function.

Aged↗
PubMed1989

[Noninvasive diagnosis of cardiac involvement by technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in 2 cases of familial amyloid polyneuropathy and 1 case of secondary amyloidosis].

To validate the significance of technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in diagnosing cardiac amyloidosis, 2 patients with familial amyloid polyneuropathy (FAP) and 1 patient with amyloidosis secondary to chronic rheumatic arthritis were studied. All three patients had echocardiographic abnormalities, which were increased wall thickness of the interventricular septum and the left ventricular posterior wall, and granular sparkling appearance in the septum. In 2 patients with FAP, abnormal myocardial uptake of Tc-99m PYP was diffusely detected in Tc-99m PYP SPECT. In the remaining 1 patient with secondary amyloidosis, however, Tc-99m PYP SPECT showed no abnormality, although we had confirmed the presence of myocardial amyloid deposits (type AA amyloid protein) with high amount in the histological examination. Thus, these results indicate that Tc-99m PYP scintigraphy may have a limitation in detecting cardiac involvement in secondary amyloidosis although it is useful in FAP.

Adult↗
PubMed1989

[Radial long-axis tomography: a new reconstructing algorithm for thallium-201 myocardial SPECT].

The long-axis (L-A) tomograms of the heart in thallium-201 SPECT have been conventionally reconstructed as those parallel to the midventricular vertical or horizontal L-A plane. We developed a new algorithm for reconstructing the rotated L-A tomograms around the L-A to longitudinally observe thallium-201 myocardial distribution and to provide an optimal view of the cardiac apex. After determining the orientation of the L-A and reconstructing the short-axis (S-A) tomograms using standard techniques, the coordinates of the S-A planes were transformed to the polar coordinates whose origin is located at the position of the L-A in each plane. Then, "radial L-A tomograms", i.e. midventricular L-A planes oriented at the angle of every 6 degrees to the midventricular horizontal L-A plane, were reconstructed. Also, we developed a new technique for analyzing thallium-201 distribution of the L-A tomograms. For the basal 2/3 regions, two profiles which consist of the pixels with maximum count on the upper and lower myocardial portions of the lines (spaced at 1 pitch) vertically to the L-A were computed. For the remaining apical 1/3 regions, the semi-circumferential maximum-count profile from the values of 30 radii spaced at 6 degrees interval were computed. Based on these profiles, a 2D polar representation was then generated. From the study using a cardiac phantom with an apical small infarction, the usefulness of this new tomographic method for the detection of apical myocardial ischemia was demonstrated. The application to the exercise/redistribution studies in patients with effort angina indicated that radial long-axis tomography provides precise information about the longitudinal extent of perfusion defects, particularly in the apical regions.

Algorithms↗
PubMed1989

[Angiomyolipoma of the kidney; report of two cases with a low fat component].

We report two cases of unilateral renal angiomyolipoma. In both cases, our preoperative diagnosis was renal cell carcinoma because no low density area compatible with a fatty tissue was noted in the tumors. Histological examination revealed both tumors to be angiomyolipoma mainly composed of myomatous cells and immature fat cells.

Adult↗
PubMed1989

[Evaluation of CT myelography and conventional myelography for avulsion injury of nerve root--18 cases of birth palsy].

CT myelography (CTM) and conventional myelography were reviewed in 18 cases of birth palsy with clinically suspected avulsion injury. A traumatic meningocele was detected in 45 roots by CTM, and in 35 roots by myelography. CTM misinterpreted only one root with a very small meningocele. CTM was superior to myelography in delineating a traumatic meningocele, because CTM is sensitive to a poorly enhanced meningocele. On the other hand, CTM missed 9 avulsed roots without a meningocele. By myelography, these 9 roots were diagnosed as 6 roots of complete avulsion injury and 3 roots of incomplete avulsion. Myelography is indispensable in evaluating nerve root avulsion.

Child↗
PubMed1989

[Regional left ventricular diastolic function in hypertrophic cardiomyopathy: application of "sector analysis" to ECG forward and reverse gated radionuclide ventriculography].

To estimate regional left ventricular (LV) diastolic filling patterns in hypertrophic cardiomyopathy (HCM), a computer-assisted method by applying "sector analysis" to ECG forward and reverse gated radionuclide ventriculography was developed. Fourteen patients with HCM (four with localized septal hypertrophy, seven with apical hypertrophy and three with septal and apical hypertrophy according to echocardiography) were observed at rest. After establishing serial 20 msec imaged frames, the LV region of interest was subdivided into eight sectors radiating from the geometric center. A time-activity curve was generated for each sector and was fitted by third-order harmonics of the Fourier series. From each fitted curve, the regional peak filling rate (rPFR) and the time of rPFR (rTPFR) in the forward gating method and regional atrial contribution to filling (rAC/FV) in the reverse gating method were calculated. The coefficient of variance of rTPFR was used as an index of LV diastolic asynchrony. In HCM, a prominent delay of rTPFR was observed in the hypertrophied regions. The coefficient of variance of rTPFR correlated inversely with global LVPFR (r = -0.62, p less than 0.05), indicating that diastolic asynchrony is one of the determinants of the LV early filling rate. Regional AC/FV was augmented in the hypertrophied regions, indicating the important role of atrial systolic LV filling for slowed early filling. Thus, this new method provides valuable information concerning regional diastolic LV wall mechanics in HCM.

Adult↗
PubMed1989

[Prognostic factors of malignant lymphoma].

Advances in staging and more refined radiation techniques and the combination chemotherapy have lead marked improvement of survival of patients with Hodgkin's disease and non-Hodgkin's lymphoma. The important prognostic factors used for choosing treatment programs are stage, histology, tumor bulk and the site of involvement for patients with early stage disease. Tumor bulk is considered as an important variable when patients are treated with radiation therapy alone. However, aggressive staging and effective therapy tend to obscure the differences in survival and relapse-free survival that would be observed in untreated patients and may be difficult to identify prognostic factors.

Combined Modality Therapy↗
PubMed1989

[Cavitating malignant neoplasms in the lung].

Cavitation was found in 8.3% of 96 primary lung cancers, and in 4.5% of 111 metastatic neoplasms. Of 13 excavating lung tumors, seven had adenocarcinoma, 3 squamous cell carcinoma, one anaplastic carcinoma, one hemangioendothelioma, and one malignant melanoma. Primary cavitary lung cancers had relatively thick walls, irregular internal and outer contours, and the location of the cavity was more often central. Excavating pulmonary metastases had smooth outer margin, more often irregular internal contour, and the location of the cavity was central. Among them, four cases had thin-walled cavity. Thin-section CT was useful in the evaluation of the margin of the tumors and the internal contour of the cavities, and in the detection of small cavities in the tumors.

Adenocarcinoma↗
PubMed1989

Microcatheter with a ball tip for hepatic embolization and intra-arterial chemotherapy.

A microcatheter used mainly for cranial arterial embolization and chemotherapy was employed for hepatic arterial embolization. The tip of the microcatheter is inflated like a small balloon which then acts as a calibrated-leak balloon. A coaxial system employing a conventional catheter for abdominal angiography combined with a propulsion chamber was used. Successful chemotherapy and embolization by Lipiodol and Spongel was carried out even in cases in whom it has been considered impossible to insert a catheter into the desired arteries.

Catheterization↗
PubMed1989

[Adverse reactions and intracranial contrast medium after myelography].

Correlation between adverse reactions and intracranial contrast media after myelography was studied. Myelography was carried out for 12 cases with metrizamide and 14 with iotrolan. In all patients, cranial CT scans were performed 18 approximately 22 hours after myelography. CT attenuation value of subarachnoid cistern was higher than the gray matter in 12 cases and lower in 14 cases. Six cases suffered from adverse reactions, but only 1 case belongs to the higher group. No correlation between adverse reactions and residual amount of contrast medium on CT was recognized.

Adult↗
PubMed1989

Trial of IgG therapy for lupus nephritis--report of two cases with a successful response.

Two cases with systemic lupus erythematosus (SLE) were treated with high-dose intravenous IgG. In patient 1, the IgG therapy dramatically improved both the lupus nephritis and serological titers for SLE. In patient 2, intravenous IgG yielded a partial remission in the lupus nephritis as well as a satisfactory decrease in proteinuria and disappearance of the skin rash characteristic of SLE. IgG therapy is suggested as possibly beneficial for the treatment of SLE based on different mechanisms from those of corticosteroid action. Further studies are needed to determine the detailed efficacy of IgG therapy for SLE.

Adult↗
PubMed1989

Determination of infarct size of acute myocardial infarction in dogs by magnetic resonance imaging and gadolinium-DTPA: comparison with indium-111 antimyosin imaging.

Acute myocardial infarctions were produced in nine dogs by ligation of the left anterior descending coronary artery. Twenty-four hours after ligation, 0.5 mM/kg of gadolinium (Gd)-DTPA was injected intravenously, followed by cardiectomy 30 min later. Indium-111 antimyosin was administered intravenously 6 hr before cardiectomy to compare the infarct size with Gd-DTPA contrast enhancement. Areas of Gd-DTPA contrast enhancement were closely correlated with those of indium-111 antimyosin uptake (r = .86), although the former showed slightly greater than the latter. Partial and complete enhancements were observed in three and six dogs, respectively. In the T1 and T2 maps, T1 relaxation times of the infarcted area showed greater T1 shortening compared with normal myocardium, whereas T2 relaxation times were not different between infarcted and normal myocardium. Thus, Gd-DTPA showed significant contrast enhancement of the infarcted area because of greater T1 shortening and the extent of Gd-DTPA contrast enhancement expressed the infarct size precisely.

Animals↗